#include<fstream>
#include<algorithm>
#define NMax 200005
using namespace std;
ifstream f("apm.in");
ofstream g("apm.out");
struct muchie
{
    int x,y,c;
}v[NMax];
int n,m;
int i;
int TT[NMax],sol[NMax],R[NMax];
int t,S;
int cmp(muchie a,muchie b)
{
    return a.c<b.c;
}
int Father(int x)
{
    while(TT[x]!=x)
    x=TT[x];
    return x;
}
void Unite(int x,int y)
{
    if(R[x]<R[y])
    TT[x]=y;
    if(R[x]>R[y])
    TT[y]=x;
    if(R[x]==R[y])
    {
        TT[x]=y;
        R[y]++;
    }
}
int main()
{
    f>>n>>m;
    for(i=1;i<=m;i++)
    f>>v[i].x>>v[i].y>>v[i].c;
    sort(v+1,v+m+1,cmp);
    for(i=1;i<=n;i++)
    TT[i]=i;
    for(i=1;i<=m;i++)
    {
        if(Father(v[i].x)!=Father(v[i].y))
        {
            S+=v[i].c;
            Unite(Father(v[i].x),Father(v[i].y));
            sol[++t]=i;
        }
    }
    g<<S<<"\n"<<n-1<<"\n";
    for(i=1;i<n;i++)
     g<<v[sol[i]].y<<" "<<v[sol[i]].x<<"\n";
     return 0;
}